/* Copyright (c) 2013, 2021, Oracle and/or its affiliates.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License, version 2.0, for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */

#ifndef OBSERVER_TRANS
#define OBSERVER_TRANS

#include <mysql/gcs/gcs_communication_interface.h>
#include "gcs_plugin_messages.h"
#include "plugin.h"

/**
  Initialize transactions observer structures.
*/
void observer_trans_initialize();

/**
  Terminate transactions observer structures.
*/
void observer_trans_terminate();

/**
  Clear server sessions opened caches.
*/
void observer_trans_clear_io_cache_unused_list();

/*
  Transaction lifecycle events observers.
*/
int group_replication_trans_before_dml(Trans_param *param, int& out);

int group_replication_trans_before_commit(Trans_param *param);

int group_replication_trans_before_rollback(Trans_param *param);

int group_replication_trans_after_commit(Trans_param *param);

int group_replication_trans_after_rollback(Trans_param *param);

extern Trans_observer trans_observer;

/*
  @class Transaction_Message
  Class to convey the serialized contents of the TCLE
 */
class Transaction_Message: public Plugin_gcs_message
{
public:
  enum enum_payload_item_type
  {
    // This type should not be used anywhere.
    PIT_UNKNOWN= 0,

    // Length of the payload item: variable
    PIT_TRANSACTION_DATA= 1,

    // No valid type codes can appear after this one.
    PIT_MAX= 2
  };

  /**
   Default constructor
   */
  Transaction_Message();
  virtual ~Transaction_Message();

  /**
    Appends IO_CACHE data to the internal buffer

    @param[in] src the IO_CACHE to copy data from

    @return true in case of error
   */
  bool append_cache(IO_CACHE *src);

protected:
  /*
   Implementation of the template methods
   */
  void encode_payload(std::vector<unsigned char>* buffer) const;
  void decode_payload(const unsigned char* buffer, const unsigned char* length);

private:
  std::vector<uchar> data;
};

/**
  Broadcasts the Transaction Message

  @param msg the message to broadcast

  @return the communication engine broadcast message error
    @retval GCS_OK, when message is transmitted successfully
    @retval GCS_NOK, when error occurred while transmitting message
    @retval GCS_MESSAGE_TOO_BIG, when message is bigger than
                                 communication engine can handle
 */
enum enum_gcs_error send_transaction_message(Transaction_Message* msg);

#endif /* OBSERVER_TRANS */
